[RFC PATCH v2 11/14] powerpc/nohash: fix hash related comments in pgtable.h

From: Christophe Leroy
Date: Fri Jun 01 2018 - 11:50:04 EST


Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/include/asm/nohash/32/pgtable.h | 4 ----
arch/powerpc/include/asm/nohash/64/pgtable.h | 18 ++++--------------
2 files changed, 4 insertions(+), 18 deletions(-)

diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
index b2d0f3d0b097..a70f7bf2248f 100644
--- a/arch/powerpc/include/asm/nohash/32/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
@@ -223,10 +223,6 @@ static inline unsigned long long pte_update(pte_t *p,
}
#endif /* CONFIG_PTE_64BIT */

-/*
- * 2.6 calls this without flushing the TLB entry; this is wrong
- * for our hash-based implementation, we fix that up here.
- */
#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
static inline int __ptep_test_and_clear_young(unsigned int context, unsigned long addr, pte_t *ptep)
{
diff --git a/arch/powerpc/include/asm/nohash/64/pgtable.h b/arch/powerpc/include/asm/nohash/64/pgtable.h
index b90256f74cc8..bf04176dbef1 100644
--- a/arch/powerpc/include/asm/nohash/64/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/64/pgtable.h
@@ -3,7 +3,7 @@
#define _ASM_POWERPC_NOHASH_64_PGTABLE_H
/*
* This file contains the functions and defines necessary to modify and use
- * the ppc64 hashed page table.
+ * the ppc64 non-hashed page table.
*/

#include <asm/nohash/64/pgtable-4k.h>
@@ -38,7 +38,7 @@

/*
* The vmalloc space starts at the beginning of that region, and
- * occupies half of it on hash CPUs and a quarter of it on Book3E
+ * occupies a quarter of it on Book3E
* (we keep a quarter for the virtual memmap)
*/
#define VMALLOC_START KERN_VIRT_START
@@ -78,7 +78,7 @@

/*
* Defines the address of the vmemap area, in its own region on
- * hash table CPUs and after the vmalloc space on Book3E
+ * after the vmalloc space on Book3E
*/
#define VMEMMAP_BASE VMALLOC_END
#define VMEMMAP_END KERN_IO_START
@@ -248,14 +248,6 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
pte_update(mm, addr, ptep, _PAGE_RW, 0, 1);
}

-/*
- * We currently remove entries from the hashtable regardless of whether
- * the entry was young or dirty. The generic routines only flush if the
- * entry was young or dirty which is not good enough.
- *
- * We should be more intelligent about this but for the moment we override
- * these functions and force a tlb flush unconditionally
- */
#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
#define ptep_clear_flush_young(__vma, __address, __ptep) \
({ \
@@ -279,9 +271,7 @@ static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
}


-/* Set the dirty and/or accessed bits atomically in a linux PTE, this
- * function doesn't need to flush the hash entry
- */
+/* Set the dirty and/or accessed bits atomically in a linux PTE */
static inline void __ptep_set_access_flags(struct mm_struct *mm,
pte_t *ptep, pte_t entry,
unsigned long address)
--
2.13.3